Conventional pneumatic tires are designed to perform for relatively long periods of time. In many cases, automobile tires are now expected to have a useful service life of 30,000, 50,000 or 70,000 miles. However, even long-life pneumatic tires are subject to air pressure losses due to puncture by nails and other sharp objects, temperature changes, and/or diffusion of air through the tire itself.
Since air diffusion reduces tire pressure over time, the pneumatic tires may repeatedly become underinflated. Accordingly, drivers must in turn repeatedly act to maintain recommended air pressures in the vehicle tires to avoid reduced fuel economy, tire life, and/or vehicle braking and handling performance. Tire pressure monitoring systems (TPMS) are automated systems that have been proposed to warn drivers when the air pressure in the vehicle tires is significantly low. Such systems, however, remain dependent upon a driver taking remedial action, when warned, to re-inflate a tire to the recommended pressure. It had thus been desirable in the prior art to incorporate an air maintenance feature within a pneumatic tire that would maintain a predetermined or recommended air pressure without requiring driver intervention.
To this end, air maintenance tire (AMT) systems have been developed. An AMT system typically includes one or more pumps or pumping assemblies that act to increase the air pressure in the vehicle tires as needed. In such AMT systems, a pumping mechanism is in fluid communication with the tire cavity. The pumping mechanism compresses air, which is then directed into the tire cavity.
For certain applications, it has been determined that an AMT system which includes components that do not require modification of the tire may be advantageous. However, it is desirable for the pumping mechanism to be disposed proximate the tire, such as on the wheel, while not interfering with assembly of the tire onto a wheel. For example, when it is proposed to mount certain components of an AMT system to a wheel, the components must allow for proper mounting of the tire on the wheel through normal mounting procedures. This may pose an issue in the construction of the AMT system, as original wheel designs typically do not have mounting surfaces for AMT components built into the wheel. It is to be understood that reference herein shall be made to the word “wheel” with the understanding that such reference includes alternate terminology that is sometimes employed in the art, such as “rim” and the like.
As a result, there is a need in the art for a wheel formed with features that enable components of an AMT system to be securely mounted to the wheel, while allowing a tire to be mounted on the wheel without interference from the AMT system components.